﻿namespace BadHabit.WPFTools
{
    using System;
    using System.IO;
    using System.Net;
    using System.Windows;
    using System.Windows.Controls;
    using System.Windows.Data;
    using System.Windows.Media;
    using System.Windows.Media.Animation;
    using System.Windows.Navigation;
    using System.ComponentModel;

    /// <summary>
    /// Extends the usual ComboBox to suport a different Template for the Selected Item.
    /// </summary>
    public class ComboBox : System.Windows.Controls.ComboBox
    {
        public static readonly DependencyProperty MaxLengthProperty = DependencyProperty.Register("EditableTextBox", typeof(int), typeof(BadHabit.WPFTools.ComboBox), new UIPropertyMetadata(int.MaxValue));

        /// <summary>
        /// DependencyProperty for the select item template.
        /// </summary>
        public static DependencyProperty SelectedItemTemplateProperty = DependencyProperty.Register("SelectedItemTemplate", typeof(DataTemplate), typeof(BadHabit.WPFTools.ComboBox));

        /// <summary>
        /// DependencyProperty for the dropdown background.
        /// </summary>
        public static DependencyProperty DropDownBackgroundProperty = DependencyProperty.Register("DropDownBackground", typeof(Brush), typeof(BadHabit.WPFTools.ComboBox));

        [Description("Maximum length of the text in the EditableTextBox.")]
        [Category("Editable ComboBox")]
        [DefaultValue(int.MaxValue)]
        public int MaxLength
        {
            [System.Diagnostics.DebuggerStepThrough]
            get
            {
                return (int)this.GetValue(MaxLengthProperty);
            }

            [System.Diagnostics.DebuggerStepThrough]
            set
            {
                this.SetValue(MaxLengthProperty, value);
                this.ApplyMaxLength();
            }
        }

        protected TextBox EditableTextBox
        {
            get
            {
                return this.GetTemplateChild("PART_EditableTextBox") as TextBox;
            }
        }

        public override void OnApplyTemplate()
        {
            base.OnApplyTemplate();
            this.ApplyMaxLength();
        }

        private void ApplyMaxLength()
        {
            if (this.EditableTextBox != null)
            {
                this.EditableTextBox.MaxLength = this.MaxLength;
            }
        }

        /// <summary>
        /// Get and set the datatemplate for the selected item.
        /// This is a dependency property.
        /// </summary>
        public DataTemplate SelectedItemTemplate
        {
            get
            {
                return (DataTemplate)GetValue(SelectedItemTemplateProperty);
            }

            set
            {
                SetValue(SelectedItemTemplateProperty, value);
            }
        }

        public Brush DropDownBackground
        {
            get
            {
                return (Brush)GetValue(DropDownBackgroundProperty);
            }

            set
            {
                SetValue(DropDownBackgroundProperty, value);
            }
        }

        /// <summary>
        /// Updates the data source.
        /// </summary>
        private void UpdateDataSource()
        {
            BindingExpression expression = GetBindingExpression(ComboBox.TextProperty);
            if (expression != null)
            {
                expression.UpdateSource();
            }
        }

        /// <summary>
        /// Updates the Text property binding when the selection changes.
        /// </summary>
        /// <param name="e">A SelectionChanged EventArgs.</param>
        protected override void OnSelectionChanged(SelectionChangedEventArgs e)
        {
            base.OnSelectionChanged(e);
            this.UpdateDataSource();
        }

        protected override void OnKeyUp(System.Windows.Input.KeyEventArgs e)
        {
            base.OnKeyUp(e);
            if (e.Key == System.Windows.Input.Key.Return || e.Key == System.Windows.Input.Key.Enter)
            {
                this.UpdateDataSource();
            }
        }
    }
}
